The present invention generally relates to sensor modules, and, more particularly, to a sensor module with a blade insert and a method of assembly therefor.
Vehicle crash detection systems use electronic sensors, such as pressure sensors and acceleration sensors, to detect impact of a vehicle with another object or vehicle. The sensors are mounted in modules, and the modules are located in crush zones of the vehicle. For example, air bag deployment systems typically employ a multitude of sensors for sensing longitudinal and/or lateral acceleration (or deceleration). Pressure sensors are generally located in the vehicle door crush zone, while acceleration sensors are located in a rigid beam, such as an A-pillar of the vehicle.
FIG. 1A is a flow chart illustrating a conventional process 10 for assembling an acceleration sensor module. In a first step 12, a sensor die is packaged, such as in a Quad Flat No-leads (QFN) type package 20, as shown in FIG. 1B. Such packaging typically involves mounting the die on a flag of a lead frame, electrically connecting the die to leads of the lead frame, over-molding, and singulation. Next, at step 14, a PCB assembly 22 is formed by mounting the packaged sensor die 20 on a printed circuit board (PCB) 24, along with a plurality of passive devices 26, such as resistors and capacitors, as shown in FIG. 1C. The PCB 24 also includes blade type leads 28 that extend from the PCB 24. Thus, the sensor die, the passive devices 26, and the leads 28 are connected by wiring within the PCB 24. At step 16, a socket-assembly 30 is formed by attaching or mounting the PCB assembly within an enclosure 32, as shown in FIG. 1D. Finally, at step 18, a housing 34 is formed around the socket-assembly 30, to form a sensor module 36, where the leaded socket assembly 30 is located in a recessed chamber within the housing 34, as shown in FIG. 1E.
The sensor module 36 may then be bolted or otherwise attached to a vehicle, and the leads 30 plugged into an electrical interface connector (not shown). While this assembly process is well known, there are many steps required to form the final sensor module. Accordingly, it would be advantageous to have a more efficient assembly process.